Add Julia GeoStats Tutorial (#7883)

* Add Julia GeoStats Tutorial

* Fix Alphabetical Ordering

courses/free-courses-en.md

@@ -778,6 +778,7 @@
 
 ### Julia
 
+* [GeoStats.jl Tutorials](https://www.youtube.com/playlist?list=PLsH4hc788Z1f1e61DN3EV9AhDlpbhhanw) - Julio Hoffimann (YouTube)
 * [Julia Tutorials (Basic)](https://www.youtube.com/playlist?list=PLP8iPy9hna6SCcFv3FvY_qjAmtTsNYHQE) - The Julia Programming Language (YouTube)